What was the most important invention in human history? The printing press? Antibiotics? Nope, says Alan Weisman in this talk from TEDxSitka. And he has a couple of simple ideas for how to undo its damage.

In speeches and media appearances, Alan Weisman argues that humane and effective ways exist to bring Earth’s human population in line with the planet’s carrying capacity.

Homelands co-founder Alan Weisman’s “Countdown: Our Last, Best Hope for a Future on Earth?” was awarded the 2013 LA Times Book Prize in the science and technology category. “Countdown” was also named the best general nonfiction book of 2013 at the Paris Book Fair and won the 2014 Population Institute Global Media Award for best book.

In Countdown, Alan proposes concrete steps for bringing human population growth back in line with the planet’s carrying capacity. He’ll share the stage tonight in LA with Amy Chua, Salman Rushdie, Andrew Sullivan, and Seth MacFarlane.

The novelist Louise Erdrich has written a glowing review of Alan Weisman’s Countdown for her blog, Birchbark. She calls the book “urgent, eloquent, harrowing yet hopeful.”

Please read this book. Take your time. You will weep and yet be cheered.

The founder and owner of Birchbark Books in Minneapolis, Erdrich is a reader’s reader (she’s a writer’s reader, too!), and a passionate advocate for independent bookstores. Her latest novel, The Round House, won the 2012 National Book Award for fiction.

We’re thrilled to announce the publication of Countdown: Our Last, Best Hope for a Future on Earth?, by Homelands senior producer and co-founder Alan Weisman. You should be able to find it in bookshops today, and if you pre-ordered it from an online seller, it should be on its way.

Every four and a half days, the world population goes up by another million. Photo by Sam Eaton.

Published by Little, Brown and Co., Countdown is Alan’s sixth book and a fitting sequel to his international bestseller, The World Without Us. In the earlier book, he looked at how the natural world might heal if freed from human pressure. In Countdown, he asks how we can bend our population curve to avoid a collision with the planet’s resource base.

If The World Without Us was a grand thought experiment, Countdown is an urgent – and practical – call to action.

Check out the book’s trailer (yes, it has a trailer!) here. Read an excerpt in Salon here. And see what the reviewers are saying here. Then go out and get a copy!

Here’s the press release from the publisher, Little, Brown and Company:

Alan Weisman’s previous book, “The World Without Us,” was a finalist for the National Book Critics Circle Award. It has been translated into 34 languages.

In his internationally bestselling book The World Without Us, Alan Weisman considered how the world could heal and even refill empty niches if relieved of humanity’s constant pressures. Behind that groundbreaking thought experiment was his hope that we would be inspired to find a way to add humans back to this vision of a restored, healthy planet—only in harmony, not mortal combat, with the rest of nature.

But with a million more of us approximately every 4 1/2 days on a planet that’s not getting any bigger, and with our exhaust overheating the atmosphere and altering the chemistry of our oceans, prospects for a sustainable future seem ever more in doubt. In Countdown: Our Last, Best Hope for a Future on Earth?, Alan Weisman’s long awaited follow-up book, he traveled to 21 countries to ask four questions that experts agreed were probably the most important on Earth—and also the hardest.

How many people can the Earth sustain?

If, in order to ensure our survival, we need to stop our growth before we hit 10 billion—or even reduce our numbers from our current 7 billion—is there an acceptable, nonviolent way to convince all of the world’s cultures, religions, nationalities, tribes, and political systems that it’s in their best interest to do so?

What kind of ecosystem is necessary to maintain human life, and what species or ecological processes are essential to our survival?

If a sustainable population on Earth is less than our current growth projection, or even less than our current number, how do we design an economy for a shrinking population, and then for a stable one—that is, for an economy not dependent on constant growth?

Truly a journalistic tour de force, Countdownis a riveting piece of narrative nonfiction that is impossible to put down, as compellingly entertaining to read as its message is urgent.

Weisman takes readers around the world to such diverse locales as Pakistan, a land the size of Texas whose numbers by midcentury will surpass today’s United States; the Philippines, where too many fishermen struggle to feed large families from increasingly depleted seas whose rising waters encroach on cropland; to Niger, with the world’s highest fertility rate, where each woman bears an average of seven to eight children; to Italy and Japan, where population has actually fallen below replacement rate: two children per two adults.

Weisman shares alarming projections about our ability to keep feeding growing multitudes, but he also reveals some startling successes, such as in Iran, where a voluntary family planning program dropped the highest rate of population growth in history to replacement level a year faster than China’s compulsory one-child policy.

By vividly detailing the burgeoning effects of our cumulative presence, Countdownreveals what may be the fastest, most acceptable, practical, technologically feasible, and affordable way of returning our planet and our presence on it to balance. Alan Weisman again shows that he is one of the most provocative journalists working today, with a book whose message is so compelling that it will change how we see our lives and our destiny.

In India, many farmers are returning to their traditional rice varieties, which often perform better than modern strains in salty soils. Meanwhile, scientists are working to incorporate salt tolerance into high-yielding varieties as stronger storms and rising seas increase the salinity of coastal fields. Photo by Sam Eaton.

One of the goals of the “Food for 9 Billion” project has been to show that keeping our growing number of selves fed (sustainably, equitably, healthily) is more than just a technical challenge.

But the technical stuff matters, too. Certainly for better-off producers and consumers, for whom small changes can have enormous consequences. But especially, I think, for small-scale, low-income farmers in developing countries, where demand is growing the fastest, productivity is growing the slowest, undernourishment is the highest, and the strains on resources are most severely felt.

Often, after these stories air, listeners or viewers write to tell us that we’re missing the point, that the real problem is ___________. The blank may be any number of things – population growth, poverty, lack of access to markets or land or credit or political power. No technology will help until we deal with that.

In a recent blog post inGrist,Tom Laskawy reports on efforts to get geeky tech types to turn their attention to improving the food system, then warns that it’s folly to expect technology to ensure “that adequate food is produced in a sustainable way for a growing population.” The piece carries the headline “When it comes to food, technology won’t save us.”

Fine. But no single thing will, and it would be a shame for people to stop innovating because their particular insight or gadget or method isn’t going to save the world on its own.

I think the agroecologists have it right – the world is complex. Everything interacts with everything else. Conditions differ in important ways from place to place, and they change over time. No single technology will work everywhere. Scratch that: no single technology will work anywhere.

That’s not to say that “all of the above” is the best way forward – some technologies, like some policies or ideas, are inappropriate or dangerous or counterproductive. But it’s unlikely that “none of the above” is the answer, either.

I never give a journalist grief for a headline (I rarely get to write mine), but maybe a better title for Laskawy’s piece (and, for that matter, for “Food for 9 Billion”) would be “When it comes to food, ________ won’t save us.”